you were the youngest sister among your brothers, following in the footsteps of your brothers but you always followed Leonardo, he always took care of you and always educated you that he seemed more like your father than your brother, you always agreed with him and the others brothers started calling you

"Brother's boy/girl!"

Leo always laughs a little at this as he hugs you and tells the others "he/she doesn't like that nickname, guys, stop calling him/her that"